/*
 * Licensed to Elasticsearch B.V. under one or more contributor
 * license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright
 * ownership. Elasticsearch B.V. licenses this file to you under
 * the Apache License, Version 2.0 (the "License"); you may
 * not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

using System.Collections.Generic;
using System.Runtime.Serialization;
using Nest.Utf8Json;

namespace Nest
{
	/// <summary>
	/// An analyzer of type pattern that can flexibly separate text into terms via a regular expression.
	/// </summary>
	public interface IPatternAnalyzer : IAnalyzer
	{
		[DataMember(Name ="flags")]
		string Flags { get; set; }

		[DataMember(Name ="lowercase")]
		[JsonFormatter(typeof(NullableStringBooleanFormatter))]
		bool? Lowercase { get; set; }

		[DataMember(Name ="pattern")]
		string Pattern { get; set; }

		/// <summary>
		/// A list of stopword to initialize the stop filter with. Defaults to an empty list
		/// </summary>
		[DataMember(Name ="stopwords")]
		StopWords StopWords { get; set; }
	}

	/// <inheritdoc />
	public class PatternAnalyzer : AnalyzerBase, IPatternAnalyzer
	{
		public PatternAnalyzer() : base("pattern") { }

		public string Flags { get; set; }

		public bool? Lowercase { get; set; }

		public string Pattern { get; set; }

		public StopWords StopWords { get; set; }
	}

	/// <inheritdoc />
	public class PatternAnalyzerDescriptor : AnalyzerDescriptorBase<PatternAnalyzerDescriptor, IPatternAnalyzer>, IPatternAnalyzer
	{
		protected override string Type => "pattern";
		string IPatternAnalyzer.Flags { get; set; }
		bool? IPatternAnalyzer.Lowercase { get; set; }
		string IPatternAnalyzer.Pattern { get; set; }

		StopWords IPatternAnalyzer.StopWords { get; set; }

		public PatternAnalyzerDescriptor StopWords(params string[] stopWords) => Assign(stopWords, (a, v) => a.StopWords = v);

		public PatternAnalyzerDescriptor StopWords(IEnumerable<string> stopWords) =>
			Assign(stopWords.ToListOrNullIfEmpty(), (a, v) => a.StopWords = v);

		public PatternAnalyzerDescriptor StopWords(StopWords stopWords) => Assign(stopWords, (a, v) => a.StopWords = v);

		public PatternAnalyzerDescriptor Pattern(string pattern) => Assign(pattern, (a, v) => a.Pattern = v);

		public PatternAnalyzerDescriptor Flags(string flags) => Assign(flags, (a, v) => a.Flags = v);

		public PatternAnalyzerDescriptor Lowercase(bool? lowercase = true) => Assign(lowercase, (a, v) => a.Lowercase = v);
	}
}
